Radius clauses have become powerful tools for music festivals. A radius clause is meant to prevent an artist on an event lineup from playing a similar event within a specific time frame. For example, the Ultra Music Festival radius clause prevents artists from playing other festivals in Florida for a certain duration. While radius clauses work well for festival organizers, they can seem anti-competitive and restricting, as one festival now claims against Coachella.

Radius clauses are now the subject of a new lawsuit between the founders of Soul’d Out Music Festival and Coachella. Nicholas Harris and Haytham Abdulhadi, founders of the Portland, Oregon music festival, have brought the lawsuit against Coachella and its organizers AEG Live and Goldenvoice.

Lawyers for Harris and Abdulhadi told Billboard that Coachella has a five-month, five-state radius clause that prevents artists on the lineup from playing other festivals. This year’s radius clause allegedly includes festivals in California, Oregon, Washington, Nevada and Arizona and runs from December 15, 2017 to May 7, 2018.

The lawyers told Billboard that Harris and Abdulhadi learned of the radius clause restrictions when attempting to book SZA, Daniel Caesar and Tank and the Bangas. The lawyers accused of Coachella and its organizers of creating “an unlawful restraint on trade, meant to use Coachella’s market power in the music festival market to suppress competition by other festivals.” Lawyer Nicholas F. Aldrich also said that the festival’s radius clause allows artists to play AEG venues at events within the radius clause, but not at competing events.

Coachella kicks off this week on April 13. The Soul’d Out Music Festival takes place in Portland, Oregon on April 18-22.